As is well known, selected electric or electronic parts radiate electromagnetic waves which can cause noise or unwanted signals to appear in electric or electronic parts and devices existing in the vicinity of the radiating parts. Accordingly, it is highly desirable to provide shielding and/or grounding for electronic components that use circuitry that emits or is susceptible to electromagnetic radiation. It is known that these components can be shielded to reduce undesirable electromagnetic interference and/or susceptibility effects with the use of a conductive shield that reflects or dissipates the electromagnetic charges and fields. Such shielding may be grounded to allow the offending electrical charges and fields to be dissipated without disrupting the operation of the electronic components enclosed within the shield.
Various types of EMI/RFI shielding devices are known for reducing the transmission of EMI and RFI. Among the known devices are gaskets or strips of a resiliently deformable material which are secured to an openable access panel, door, drawer, or the like (hereinafter "door"), to block the transmission of EMI/RFI through the small clearance between the door and the adjacent structure which forms the opening into and out of which the door is movable. Such strips are useful for shielding openings of housings for electronic components which are highly sensitive to the adverse effects of EMI/RFI.
Such known devices are typically made of one of several materials which have the combined functions of acting as an EMI/RFI shield, and which are resiliently deformable so that they can be compressed between the door when closed, and will spring back to an uncompressed configuration when the door is moved out of the opening. U.S. patent application Ser. No. 08/819,983, filed Mar. 18, 1997, entitled "SELF-TERMINATING, KNITTED METALIZED YARN EMI/RFI SHIELDING GASKET," which is hereby incorporated by reference, provides examples of such gaskets.
Prior shielding strips, although providing an adequate level of shielding for the electronic devices, are often difficult to install on an electronics housing and are often not secured to a mounting surface to withstand the forces generated in use without detaching from the surface. For example, one prior strip utilizes a track which is riveted to the mounting surface of the housing, the shielding strip then being slid onto the riveted track to hold the strip in place. Although providing a secure mount for the shielding strip, the riveted track involves a relatively complicated installation procedure, involving several steps, and is therefore labor intensive. Furthermore, a shielding strip which requires a riveted track is relatively expensive, because it requires extra parts (a track and rivets), and added labor to install. The riveted track is also somewhat prone to misinstallation, because installation requires alignment of a rivet with holes in the track. U.S. patent application Ser. No. 09/139,654, entitled "MOUNTING SYSTEM AND METHOD FOR MOUNTING TRACK HAVING BARBED RIVETS," by Anthony Michael Sosnowski, filed Aug. 25, 1998, which is hereby incorporated by reference, discloses a mounting system including a track having compressible barbs that extend through holes in a housing wall to secure the mounting track to the wall.
One difficulty with most prior art gasket mounting arrangements is that, in mounting the gasket around a structure such as a door, it is difficult, if not impossible to bend the mounting arrangement, which typically includes a thin steel or plastic track, i.e., a substantially planar track, around bends because doing so would involve bending the track in its plane. While the track might be easily bendable out of the original plane, it will typically fold up at corners when bent in its plane, risking a poor seal at the corners. Solutions to this problem have included using multiple gasket/track arrangements around bends, and forming mounting arrangements having the specific shape of the wall to which they are to be mounted. The multiple mounting arrangement solution is not highly desirable because substantial installation work is necessary, it is typically unsightly, and gaps may exist between adjacent mounting arrangements, thus defeating the shielding function. It has not typically been desirable to form mounting arrangements for specific mounting applications, i.e., for specific, unique or limited quantity shapes, because of the comparatively high cost involved in forming a track for the special application, which usually includes cutting a track shape from a plate of material or joining together track sections, as compared with typical track arrangements that can be mass produced at relatively low cost.
It is desirable to provide a mounting arrangement and method for mounting gasket arrangements that is inexpensive and simple to install. It is also desirable to provide a mounting arrangement that can be attached to a wall around bends with minimal difficulty, and without the need for using multiple track sections. It is also desirable to provide a mounting arrangement that can be produced in a simple manner for mounting on complex shapes.
According to an embodiment of the present invention, a retention clip track includes a substantially flat track having a first surface, a second surface, a first edge extending between the first surface and the second surface, and a second edge extending between the first surface and the second surface on an opposite side of the track from the first edge. At least one clip extends from the first edge, the clip and the track together forming a substantially C-shaped structure. The track has a plurality of adjacent saw tooth-shaped recesses extending from at least one of the second edge toward the first edge and the first edge toward the second edge.
According to another embodiment of the present invention, a gasket arrangement includes a gasket and a retention clip track. The retention clip track includes a substantially flat track having a first surface, a second surface, a first edge extending between the first surface and the second surface and a second edge extending between the first surface and the second surface on an opposite side of the track from the first edge. At least one clip extending from the first edge, the clip and the track together forming a substantially C-shaped structure. The track has a plurality of adjacent saw tooth-shaped recesses extending from at least one of the second edge toward the first edge and the first edge toward the second edge. The gasket is attached to the track.
According to yet another embodiment of the present invention, a method is disclosed for securing a gasket arrangement to a wall, the wall having a first surface, a second surface, and an edge between the first and the second surface, and the edge having at least one non-linear portion. According to the method, a longitudinal track is provided with a plurality of tabs that extend laterally from a first edge of the track. A plurality of saw tooth-shaped recesses is formed in the track such that the recesses extend from at least one of second edge of the track toward the first edge and a first edge of the track toward the second edge of the track. The plurality of tabs are bent relative to track so that the tabs and the track together form substantially C-shaped clips. A gasket is attached to a surface of the track to form a gasket arrangement. The gasket arrangement is bent at the saw teeth-shaped recesses of the track so that the gasket arrangement conforms generally to a shape of the edge of the wall. The gasket arrangement is secured to the wall by fitting the wall in the clips formed by the tabs and the track.
According to still another embodiment of the present invention, a method is disclosed for making a gasket arrangement for attachment to a wall, the wall having a first surface, a second surface, and an edge between the first and the second surface, and the edge having at least one non-linear portion. According to the method, a longitudinal track is provided with a plurality of tabs that extend laterally from a first edge of the track. A plurality of saw tooth-shaped recesses is formed in the track such that the recesses extend from at least one of second edge of the track toward the first edge and a first edge of the track toward the second edge of the track. The plurality of tabs are bent relative to track so that the tabs and the track together form substantially C-shaped clips. A gasket is attached to a surface of the track to form a gasket arrangement.
It will be appreciated that, although a preferred embodiment of the present invention is as a mounting system and method for mounting shielding strips, the present invention has numerous applications in other fields where it is desirable to mount items relative to one another.